Many compounds for medical use are packaged separately from the diluents used to reconstitute or dilute them, and facilitate their intravenous or subcutaneous delivery to a patient. These medical compounds are packaged in a variety of known pharmaceutical containers (e.g., vials) in solid form (e.g., lyophilized or spray-dried), liquid form, and other forms. Prior to administration of these compounds to a patient, the compounds are mixed with the diluents. If desired, the diluents can contain additional active compounds.
In order to mix a compound with a diluent, it is desirable to provide a system for mixing the compound and diluent that does not expose the compound, diluent, or resulting mixture to the external environment prior to and during mixing. Such exposure could negatively affect the sterility of the mixture, or, in the case of hazardous compounds, could place the user (e.g., a healthcare worker) in danger by exposing them to the hazardous compounds.
Systems for facilitating the safe transfer and mixing of medical compounds and diluents stored in separate containers are known. For example, a system involving the packaging of a medicament and a diluent in separate containers, which may be connected to one another at the time of use for convenient and safe mixing of the medicament and diluent in a sterile environment is currently sold by Hospira, Inc. (Lake Forest, Ill.) under the trademark ADD-VANTAGE®. The ADD-VANTAGE® system is described in U.S. Pat. Nos. 4,703,864; 4,757,911; 4,784,259; 4,784,658; 4,936,445; 4,948,000; 5,064,059; and 5,332,399, each of which is incorporated herein by reference in its entirety.
In one example of the ADD-VANTAGE® system, a flexible diluent container includes a receiving port configured to receive a medicament vial closed by a vial stopper. The receiving port is positioned at the top end of the diluent container (i.e., the end of the diluent container that is on top when the diluent container is hung for delivery of its contents to a patient). The flexible diluent container further includes a stopper removal member configured to connect to the vial stopper by engaging an undercut or shouldered recess in the exposed end of the vial stopper. Securement of the vial and the diluent container is accomplished by threadable engagement of threads that circumscribe the outside of the neck portion (which defines the vial opening) of the vial with complementary threads within the diluent container port. Additionally, ratchet teeth, which circumscribe the outside of a skirt member of the vial, engage complementary ratchet teeth located on the interior of the diluent container port. The slopes of the ratchet teeth are such that once engagement is initiated, the vial cannot be backed out of the port without causing visible damage to the vial and/or port, thereby obviating any contamination which may be occasioned by vial-container disengagement and reengagement. In other words, the ratchet teeth are “one-way” ratchet teeth. As the stoppered vial is advanced into and engaged with the port of the diluent container, the vial stopper advances onto the stopper removal member. The stopper removal member is thereby secured to the stopper such that the stopper may subsequently be pulled and removed (via manipulation of the stopper removal member) from the vial, thereby allowing the contents of the two containers to be mixed. The system can then be hung for delivery of the mixture to a patient. To hang the system, the vial is provided with a hanger at its proximal end (i.e., the end opposite the stopper).
The flow path created as a result of activating the stopper removal member of the ADD-VANTAGE® system is defined by the neck of the vial and the dimension of the flow channel defined through the port of the diluent container. The dimension of this flow path is sufficient to permit the contents of the diluent container to flow readily into and out of the vial, (e.g., by “sloshing” the diluent container). By providing significant flow of fluid between the vial and the diluent container, the ADD-VANTAGE® system provides quick and thorough mixing. Further, because the vial is positioned at the top end of the diluent container when the contents of the diluent container are delivered to a patient, any contents remaining in the vial will flow downward into the diluent container.
Another example of a delivery system similar to the ADD-VANTAGE® system is disclosed in U.S. Pat. No. 8,216,207, which is incorporated herein by reference in its entirety. This patent describes a connector that establishes fluid communication between a medicament vial and a diluent container using a feature that pushes the stopper of a medicament vial into the vial upon connecting the medicament vial to the diluent container via the connector. Then upon further insertion of the medicament vial into the connector, the stopper of the diluent container is dislodged thereby establishing fluid communication between the medicament vial and the diluent container.
Another example of a system for transferring and mixing medical compounds and diluents stored in separate containers is the add-EASE binary connector sold by B. Braun Medical, Inc. A first end of the add-EASE connector includes a structure for receiving and securing the connector to a pharmaceutical vial. The first end includes a first spike for penetrating an elastomeric stopper sealing the vial. The second end of the add-EASE connector includes a structure for receiving and securing the connector to a port of a diluent container. The second end also includes a second spike for penetrating an elastomeric closure associated with the port of the diluent container. Once the add-EASE connector has been secured to both the vial and the diluent container, pressure is applied to the contents of the diluent container. This pressure results in a force being applied to a plug member positioned within the first spike, thereby moving the plug from the first spike and into the vial. Because of the relatively narrow flow channel defined by the first and second spikes of the add-EASE connector, it is necessary to pump or “milk” diluent out of the diluent container and into the vial in order to reconstitute and/or dilute the drug contained in the vial. It also is necessary to pump or “milk” the resulting diluent/drug mixture out of the vial back into the diluent container for delivery to the patient. Further, because the diluent container port is positioned at the bottom of the diluent container (i.e., at the end of the diluent container that is positioned closest to the floor when the contents of the diluent container are delivered to a patient) the dimension of the flow channel defined by the first and second spikes must remain small in order to prevent contents of the diluent container from flowing back into the vial (rather than flowing to the patient).
While the above described systems provide solutions for certain medication delivery challenges, the inventors have identified a need in the art for an improved system for mixing substances that provides more convenience and handling, and improves operator and patient safety.